This invention pertains to the automotive emissions control art, and more particularly to a method and apparatus for deflecting or redistributing the flow of exhaust gases discharged from an exhaust pipe into a canister or housing containing a coated honeycomb monolith of a catalytic converter of larger cross-sectional area than the exhaust pipe, so as to more evenly distribute such discharge flow through such catalyzed honeycomb support member within the container, and thereby optimize the treatment and removal of pollutants from said exhaust gases.
When attempting to remove pollutants from exhaust gases being emitted from the exhaust pipe of an internal combustion engine by passing such gases through a suitable catalyst support of larger cross-sectional area than the exhaust pipe, it has been found that the high velocity kinetic energy of the exhaust gas stream does not dissipate when passing from the relatively small diameter exhaust pipe into the catalyst support chamber of substantially larger diameter. Accordingly, the high velocity gases tend to merely flow through the center of the catalyst support, with a rather small proportion passing through the remainder thereof, thereby materially reducing the overall potential efficiency of the catalytic converter.
A common method of obtaining a uniform flow front has been to utilize a long frusto-conical diffuser when making a transition from a small diameter passageway to one of substantially larger cross section. A diffuser having an included angle of about 11.degree. would be ideal for maximizing the conversion of stream kinetic energy to potential energy and maintain a substantially even flow front, however, in the case of an automobile exhaust system, such a diffuser would be impractical due to the length which would be required to make such a transition. Accordingly, the present invention not only provides a substantially improved flow distribution of the exhaust gases across the face of the catalytic converter, thus providing improved efficiencies, but also accomplishes such end with a novel compact structure which is easy to fabricate and install.